US8190575B1 - Disk drive maintaining multiple copies of code segments - Google Patents

Disk drive maintaining multiple copies of code segments Download PDF

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Publication number
US8190575B1
US8190575B1 US12/199,091 US19909108A US8190575B1 US 8190575 B1 US8190575 B1 US 8190575B1 US 19909108 A US19909108 A US 19909108A US 8190575 B1 US8190575 B1 US 8190575B1
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Prior art keywords
disk
code segments
area
backup area
primary
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US12/199,091
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Choo-Bhin Ong
An-Chieh Chang
Raffi Codilian
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Western Digital Technologies Inc
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Western Digital Technologies Inc
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    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/18—Error detection or correction; Testing, e.g. of drop-outs
    • G11B20/1883—Methods for assignment of alternate areas for defective areas
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
    • G11B20/10—Digital recording or reproducing
    • G11B20/18—Error detection or correction; Testing, e.g. of drop-outs
    • G11B20/1883—Methods for assignment of alternate areas for defective areas
    • G11B2020/1893—Methods for assignment of alternate areas for defective areas using linear replacement to relocate data from a defective block to a non-contiguous spare area, e.g. with a secondary defect list [SDL]
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B2220/00—Record carriers by type
    • G11B2220/20—Disc-shaped record carriers
    • G11B2220/25—Disc-shaped record carriers characterised in that the disc is based on a specific recording technology
    • G11B2220/2508—Magnetic discs
    • G11B2220/2516—Hard disks

Definitions

  • Disk drives comprise a disk and a head connected to a distal end of an actuator arm which is rotated about a pivot by a voice coil motor (VCM) to position the head radially over the disk.
  • VCM voice coil motor
  • the disk comprises a plurality of radially spaced, concentric tracks for recording user data sectors and servo sectors.
  • the servo sectors comprise head positioning information (e.g., a track address) which is read by the head and processed by a servo control system to control the velocity of the actuator arm as it seeks from track to track.
  • the disk drive comprises control circuitry including a microprocessor for executing code segments to carry out access operations received from a host.
  • the code segments are stored in a reserved area of the disk and read into a volatile semiconductor memory (e.g., a DRAM) when the disk drive is powered on.
  • a volatile semiconductor memory e.g., a DRAM
  • Prior art disk drives store a primary copy of the code segments in a primary area of the disk, and a backup copy of the code segments in a backup area of the disk. If an error occurs while reading the primary copy of code segments from the primary area of the disk, the backup copy of code segments are read from the backup area of the disk and copied to the primary area of the disk. However, if the backup copy of code segments becomes unrecoverable due, for example, to a grown defect, it typically renders the disk drive inoperable.
  • FIG. 1A shows a disk drive according to an embodiment of the present invention comprising a disk, a head actuated over the disk, and control circuitry.
  • FIG. 1B is a flow diagram executed by the control circuitry according to an embodiment wherein code segments from a primary area of the disk are copied to a backup area of the disk.
  • FIG. 2 is a flow diagram executed by the control circuitry according to an embodiment wherein code segments are copied from the backup area to the primary area when reading from the primary area fails.
  • FIG. 3 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified periodically.
  • FIG. 4 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when an error occurs while accessing one of the primary and backup areas.
  • FIG. 5 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a shock occurs while accessing one of the primary and backup areas.
  • FIG. 6 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a read error occurs while reading data from the primary area of the disk.
  • FIG. 7 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a write error occurs while writing data to the primary area of the disk.
  • FIG. 8 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a write operation to one of the primary and backup areas is aborted.
  • FIG. 9 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a number of write operations to one of the primary and backup areas exceeds a threshold.
  • FIG. 10 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the primary area are verified when an error occurs while accessing the backup area.
  • FIG. 11 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the primary area are verified when an error occurs while writing data to the backup area of the disk.
  • FIG. 12 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the primary area are verified when a shock occurs while accessing the backup area.
  • FIG. 13 is a flow diagram executed by the control circuitry according to an embodiment wherein when data cannot be copied from the primary area to the backup area due to a defect on the disk, a data sector in the backup area is relocated to a spare sector.
  • FIG. 1A shows a disk drive according to an embodiment of the present invention comprising a disk 2 , a head 4 actuated over the disk 2 , and control circuitry 6 .
  • FIG. 1B is a flow diagram executed by the control circuitry 6 wherein code segments are written to a primary area of the disk (step 8 ) and are also written to a backup area of the disk (step 10 ).
  • the control circuitry is ready to access the code segments (step 12 )
  • the code segments are read from the primary area of the disk and executed by the control circuitry (step 14 ).
  • the control circuitry verifies the recoverability of the code segments from the backup area (step 16 ).
  • the control circuitry copies code segments from the primary area to the backup area (step 20 ).
  • the disk 2 comprises a plurality of embedded servo sectors 22 0 - 22 N which define a number of data tracks 24 .
  • Each servo sector 22 comprising coarse head positioning information (e.g., a track address) and fine head positioning information (e.g., servo bursts).
  • the control circuitry 6 processes the read signal 26 to demodulate the servo sectors 22 0 - 22 N into a position error signal representing an error between a current radial location of the head 4 and a target radial location.
  • the control circuitry 6 filters the position error signal with a suitable compensation filter to generate a control signal 28 applied to a voice coil motor (VCM) 30 which rotates an actuator arm 32 about a pivot in a direction that reduces the position error signal.
  • VCM voice coil motor
  • the code segments may be accessed by the control circuitry in connection with any suitable operating mode, such as when the disk drive needs to access boot code segments when initially powered on.
  • any suitable operating mode such as when the disk drive needs to access boot code segments when initially powered on.
  • corresponding code segments may need to be read from the disk and executed.
  • FIG. 2 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B . If an error occurs while reading the code segments from the primary area (step 34 ), then the code segments are copied from the backup area to the primary area (step 36 ). The code segments read from both the primary and secondary areas are executed (step 38 ). When the code segments are accessed again, the control circuitry first attempts to read the code segments from the primary area.
  • FIG. 3 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B wherein the control circuitry periodically verifies recoverability of the code segments from the backup area.
  • the control circuitry may verify the recoverability of the code segments from the backup area when a timer expires (step 40 ).
  • the timer may track any suitable interval, and in one embodiment, the interval may span the time when the disk drive is powered off. This embodiment may help prevent the backup area from becoming unrecoverable due to degradation of the recorded data over time (magnetic entropy).
  • FIG. 4 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B . If the control circuitry attempts to access one of the primary and secondary areas (step 42 ) and there is an error (step 44 ), then the control circuitry verifies recoverability of the code segments from the backup area. For example, in embodiments described below, a read error may occur if a number of bit errors detected exceeds a threshold, or a write error may occur if the position error signal generated from reading the servo sectors exceeds a threshold.
  • the control circuitry may verify the recoverability of the backup area if a shock event is detected (step 44 ) while accessing at least one of the primary area and the backup area. In one embodiment, the control circuitry may verify recoverability of both the primary area and the backup area if a shock event is detected when accessing either area. When a shock event is detected, particularly when writing data to the disk, it becomes more likely that the shock event may degrade the area being accessed. Therefore, if a shock event is detected while accessing the primary area, the primary area may be verified and then the backup area may be verified to ensure recoverability even if the primary area passes the verification.
  • the shock event may be detected in any suitable manner, such as by evaluating the position error signal generated when reading the servo sectors, or with a mechanical sensor (e.g., an accelerometer).
  • FIG. 6 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B . If the control circuitry executes a read operation to read data from the primary area (step 42 ), and an error is detected during the read operation (step 44 ), then the control circuitry verifies recoverability of the backup area. Any suitable error may be detected, for example, if the number of bit errors detected using an error correction code exceeds a threshold indicating that a data sector may be degrading due to a growing defect. Therefore, the backup area is verified to ensure that it can still be accessed in the event that the primary area becomes unrecoverable.
  • FIG. 7 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B . If the control circuitry executes a write operation to write data to the primary area (step 42 ), and an error is detected during the write operation (step 44 ), then the control circuitry verifies recoverability of the backup area. Any suitable error may be detected, for example, if the position error signal generated from reading the servo sectors exceeds a threshold indicating a potential problem when attempting to read the servo data. Therefore, the backup area is verified to ensure that it can still be accessed in the event that the primary area becomes unrecoverable.
  • FIG. 8 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B . If the control circuitry executes a write operation to write data to one of the primary area and backup area (step 42 ), and the write operation is aborted (step 44 ), then the control circuitry verifies recoverability of the backup area.
  • the write operation may be aborted for any suitable reason, such as an excessive position error signal generated from reading the servo sectors, which may be caused by the servo sectors degrading over time. Therefore, the backup area is verified to ensure that it can still be accessed in the event that the primary area becomes unrecoverable. In one embodiment, the backup area is verified before attempting to re-execute the write operation to the primary area to ensure the backup area is recoverable before a bad write operation renders the primary area unrecoverable.
  • FIG. 9 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B . If the control circuitry executes a number of write operations to one of the primary area and backup area (step 46 ), and the number exceeds a threshold (step 48 ), then the control circuitry verifies recoverability of the backup area. Write operations can degrade previously written data due to adjacent track interference. Therefore, the backup area is verified to ensure that it can still be accessed in the event either the primary area or backup area are degrading due to excessive write operations.
  • FIG. 10 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B .
  • the control circuitry attempts to access the backup area (step 42 ) and there is an error (step 44 )
  • the control circuitry verifies recoverability of the code segments from the primary area (step 50 ). If the verification fails (step 52 ) then the code segments are copied from the backup area to the primary area (step 54 ).
  • the control circuitry may verify the recoverability of the primary area if an error occurs (step 44 ) while writing data to the backup area of the disk (step 42 ).
  • the control circuitry may verify the recoverability of the primary area if a shock is detected (step 44 ) while accessing the backup area.
  • FIG. 13 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B .
  • the control circuitry attempts to copy the code segments from the primary area to the backup area (step 20 ).
  • the copy operation may also fail (step 56 ) if, for example, there is a grown defect in the backup area that renders a data sector within the backup area unusable.
  • An unusable data sector may be detected by performing a write verify operation wherein recoverability of a written data sector is verified after the write operation.
  • the control circuitry relocates a defective data sector in the backup area to a spare sector in the backup area, and then copies the code segments to the spare sector (step 58 ).
  • control circuitry may be implemented within a read channel integrated circuit, or in a component separate from the read channel, such as a disk controller, or certain steps described above may be performed by a read channel and others by a disk controller.
  • the read channel and disk controller are implemented as separate integrated circuits, and in an alternative embodiment they are fabricated into a single integrated circuit or system on a chip (SOC).
  • the control circuitry may include a suitable preamp circuit implemented as a separate integrated circuit, integrated into the read channel or disk controller circuit, or integrated into an SOC.
  • control circuitry comprises a microprocessor executing instructions, the instructions being operable to cause the microprocessor to perform the steps of the flow diagrams described herein.
  • the instructions may be stored in any computer-readable medium. In one embodiment, they may be stored on a non-volatile semiconductor memory external to the microprocessor, or integrated with the microprocessor in a SOC. In another embodiment, the instructions are stored on the disk and read into a volatile semiconductor memory when the disk drive is powered on. In yet another embodiment, the control circuitry comprises suitable logic circuitry, such as state machine circuitry.

Abstract

A disk drive is disclosed comprising a disk, and a head actuated over the disk. Control circuitry within the disk drive is operable to write a plurality of code segments to a primary area of the disk, and write the code segments to a backup area of the disk. The control circuitry reads the code segments from the primary area of the disk and executes the code segments read from the primary area of the disk. After reading the code segments from the primary area of the disk and executing the code segments, the control circuitry verifies recoverability of the code segments from the backup area of the disk, and when the verification fails, copies the code segments from the primary area of the disk to the backup area of the disk.

Description

BACKGROUND Description of the Related Art
Disk drives comprise a disk and a head connected to a distal end of an actuator arm which is rotated about a pivot by a voice coil motor (VCM) to position the head radially over the disk. The disk comprises a plurality of radially spaced, concentric tracks for recording user data sectors and servo sectors. The servo sectors comprise head positioning information (e.g., a track address) which is read by the head and processed by a servo control system to control the velocity of the actuator arm as it seeks from track to track.
The disk drive comprises control circuitry including a microprocessor for executing code segments to carry out access operations received from a host. The code segments are stored in a reserved area of the disk and read into a volatile semiconductor memory (e.g., a DRAM) when the disk drive is powered on. Prior art disk drives store a primary copy of the code segments in a primary area of the disk, and a backup copy of the code segments in a backup area of the disk. If an error occurs while reading the primary copy of code segments from the primary area of the disk, the backup copy of code segments are read from the backup area of the disk and copied to the primary area of the disk. However, if the backup copy of code segments becomes unrecoverable due, for example, to a grown defect, it typically renders the disk drive inoperable.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A shows a disk drive according to an embodiment of the present invention comprising a disk, a head actuated over the disk, and control circuitry.
FIG. 1B is a flow diagram executed by the control circuitry according to an embodiment wherein code segments from a primary area of the disk are copied to a backup area of the disk.
FIG. 2 is a flow diagram executed by the control circuitry according to an embodiment wherein code segments are copied from the backup area to the primary area when reading from the primary area fails.
FIG. 3 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified periodically.
FIG. 4 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when an error occurs while accessing one of the primary and backup areas.
FIG. 5 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a shock occurs while accessing one of the primary and backup areas.
FIG. 6 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a read error occurs while reading data from the primary area of the disk.
FIG. 7 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a write error occurs while writing data to the primary area of the disk.
FIG. 8 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a write operation to one of the primary and backup areas is aborted.
FIG. 9 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the backup area are verified when a number of write operations to one of the primary and backup areas exceeds a threshold.
FIG. 10 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the primary area are verified when an error occurs while accessing the backup area.
FIG. 11 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the primary area are verified when an error occurs while writing data to the backup area of the disk.
FIG. 12 is a flow diagram executed by the control circuitry according to an embodiment wherein the code segments in the primary area are verified when a shock occurs while accessing the backup area.
FIG. 13 is a flow diagram executed by the control circuitry according to an embodiment wherein when data cannot be copied from the primary area to the backup area due to a defect on the disk, a data sector in the backup area is relocated to a spare sector.
 DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
FIG. 1A shows a disk drive according to an embodiment of the present invention comprising a disk 2, a head 4 actuated over the disk 2, and control circuitry 6. FIG. 1B is a flow diagram executed by the control circuitry 6 wherein code segments are written to a primary area of the disk (step 8) and are also written to a backup area of the disk (step 10). When the control circuitry is ready to access the code segments (step 12), the code segments are read from the primary area of the disk and executed by the control circuitry (step 14). Thereafter, the control circuitry verifies the recoverability of the code segments from the backup area (step 16). When the verification fails (step 18), the control circuitry copies code segments from the primary area to the backup area (step 20).
In the embodiment of FIG. 1A, the disk 2 comprises a plurality of embedded servo sectors 22 0-22 N which define a number of data tracks 24. Each servo sector 22 comprising coarse head positioning information (e.g., a track address) and fine head positioning information (e.g., servo bursts). The control circuitry 6 processes the read signal 26 to demodulate the servo sectors 22 0-22 N into a position error signal representing an error between a current radial location of the head 4 and a target radial location. The control circuitry 6 filters the position error signal with a suitable compensation filter to generate a control signal 28 applied to a voice coil motor (VCM) 30 which rotates an actuator arm 32 about a pivot in a direction that reduces the position error signal.
The code segments may be accessed by the control circuitry in connection with any suitable operating mode, such as when the disk drive needs to access boot code segments when initially powered on. In an alternative embodiment, when the disk drive enters a particular operating mode (e.g., entering a performance mode) corresponding code segments may need to be read from the disk and executed.
FIG. 2 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. If an error occurs while reading the code segments from the primary area (step 34), then the code segments are copied from the backup area to the primary area (step 36). The code segments read from both the primary and secondary areas are executed (step 38). When the code segments are accessed again, the control circuitry first attempts to read the code segments from the primary area.
FIG. 3 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B wherein the control circuitry periodically verifies recoverability of the code segments from the backup area. For example, the control circuitry may verify the recoverability of the code segments from the backup area when a timer expires (step 40). The timer may track any suitable interval, and in one embodiment, the interval may span the time when the disk drive is powered off. This embodiment may help prevent the backup area from becoming unrecoverable due to degradation of the recorded data over time (magnetic entropy).
FIG. 4 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. If the control circuitry attempts to access one of the primary and secondary areas (step 42) and there is an error (step 44), then the control circuitry verifies recoverability of the code segments from the backup area. For example, in embodiments described below, a read error may occur if a number of bit errors detected exceeds a threshold, or a write error may occur if the position error signal generated from reading the servo sectors exceeds a threshold.
In an embodiment shown in FIG. 5, the control circuitry may verify the recoverability of the backup area if a shock event is detected (step 44) while accessing at least one of the primary area and the backup area. In one embodiment, the control circuitry may verify recoverability of both the primary area and the backup area if a shock event is detected when accessing either area. When a shock event is detected, particularly when writing data to the disk, it becomes more likely that the shock event may degrade the area being accessed. Therefore, if a shock event is detected while accessing the primary area, the primary area may be verified and then the backup area may be verified to ensure recoverability even if the primary area passes the verification. The shock event may be detected in any suitable manner, such as by evaluating the position error signal generated when reading the servo sectors, or with a mechanical sensor (e.g., an accelerometer).
FIG. 6 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. If the control circuitry executes a read operation to read data from the primary area (step 42), and an error is detected during the read operation (step 44), then the control circuitry verifies recoverability of the backup area. Any suitable error may be detected, for example, if the number of bit errors detected using an error correction code exceeds a threshold indicating that a data sector may be degrading due to a growing defect. Therefore, the backup area is verified to ensure that it can still be accessed in the event that the primary area becomes unrecoverable.
FIG. 7 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. If the control circuitry executes a write operation to write data to the primary area (step 42), and an error is detected during the write operation (step 44), then the control circuitry verifies recoverability of the backup area. Any suitable error may be detected, for example, if the position error signal generated from reading the servo sectors exceeds a threshold indicating a potential problem when attempting to read the servo data. Therefore, the backup area is verified to ensure that it can still be accessed in the event that the primary area becomes unrecoverable.
FIG. 8 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. If the control circuitry executes a write operation to write data to one of the primary area and backup area (step 42), and the write operation is aborted (step 44), then the control circuitry verifies recoverability of the backup area. The write operation may be aborted for any suitable reason, such as an excessive position error signal generated from reading the servo sectors, which may be caused by the servo sectors degrading over time. Therefore, the backup area is verified to ensure that it can still be accessed in the event that the primary area becomes unrecoverable. In one embodiment, the backup area is verified before attempting to re-execute the write operation to the primary area to ensure the backup area is recoverable before a bad write operation renders the primary area unrecoverable.
FIG. 9 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. If the control circuitry executes a number of write operations to one of the primary area and backup area (step 46), and the number exceeds a threshold (step 48), then the control circuitry verifies recoverability of the backup area. Write operations can degrade previously written data due to adjacent track interference. Therefore, the backup area is verified to ensure that it can still be accessed in the event either the primary area or backup area are degrading due to excessive write operations.
FIG. 10 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. If the control circuitry attempts to access the backup area (step 42) and there is an error (step 44), then the control circuitry verifies recoverability of the code segments from the primary area (step 50). If the verification fails (step 52) then the code segments are copied from the backup area to the primary area (step 54). For example, in an embodiment shown in FIG. 11 the control circuitry may verify the recoverability of the primary area if an error occurs (step 44) while writing data to the backup area of the disk (step 42). In an embodiment shown in FIG. 12, the control circuitry may verify the recoverability of the primary area if a shock is detected (step 44) while accessing the backup area.
FIG. 13 is a flow diagram according to an embodiment of the present invention which expands the flow diagram of FIG. 1B. When the verification of the backup area fails (step 18), the control circuitry attempts to copy the code segments from the primary area to the backup area (step 20). However, the copy operation may also fail (step 56) if, for example, there is a grown defect in the backup area that renders a data sector within the backup area unusable. An unusable data sector may be detected by performing a write verify operation wherein recoverability of a written data sector is verified after the write operation. When the copy operation fails (step 56), the control circuitry relocates a defective data sector in the backup area to a spare sector in the backup area, and then copies the code segments to the spare sector (step 58).
Any suitable control circuitry may be employed to implement the flow diagrams in the embodiments of the present invention, such as any suitable integrated circuit or circuits. For example, the control circuitry may be implemented within a read channel integrated circuit, or in a component separate from the read channel, such as a disk controller, or certain steps described above may be performed by a read channel and others by a disk controller. In one embodiment, the read channel and disk controller are implemented as separate integrated circuits, and in an alternative embodiment they are fabricated into a single integrated circuit or system on a chip (SOC). In addition, the control circuitry may include a suitable preamp circuit implemented as a separate integrated circuit, integrated into the read channel or disk controller circuit, or integrated into an SOC.
In one embodiment, the control circuitry comprises a microprocessor executing instructions, the instructions being operable to cause the microprocessor to perform the steps of the flow diagrams described herein. The instructions may be stored in any computer-readable medium. In one embodiment, they may be stored on a non-volatile semiconductor memory external to the microprocessor, or integrated with the microprocessor in a SOC. In another embodiment, the instructions are stored on the disk and read into a volatile semiconductor memory when the disk drive is powered on. In yet another embodiment, the control circuitry comprises suitable logic circuitry, such as state machine circuitry.

Claims (24)

1. A disk drive comprising:
a disk;
a head actuated over the disk; and
control circuitry operable to:
write a plurality of code segments to a primary area of the disk;
write the code segments to a backup area of the disk;
read the code segments from the primary area of the disk and execute the code segments read from the primary area of the disk;
after reading the code segments from the primary area of the disk and executing the code segments, verify recoverability of the code segments from the backup area of the disk; and
when the verification fails, copy the code segments from the primary area of the disk to the backup area of the disk.
2. The disk drive as recited in claim 1, wherein the control circuitry is further operable to periodically verify recoverability of the code segments from the backup area of the disk.
3. The disk drive as recited in claim 1, wherein the control circuitry is further operable to verify recoverability of the code segments from the backup area of the disk when an error occurs while accessing one of the primary area and the backup area of the disk.
4. The disk drive as recited in claim 3, wherein the control circuitry is further operable to verify recoverability of the code segments from the backup area of the disk when a shock event occurs while accessing one of the primary area and backup area of the disk.
5. The disk drive as recited in claim 3, wherein the control circuitry is further operable to verify recoverability of the code segments from the backup area of the disk when an error occurs while reading from the primary area of the disk.
6. The disk drive as recited in claim 3, wherein the control circuitry is further operable to verify recoverability of the code segments from the backup area of the disk when an error occurs while writing to the primary area of the disk.
7. The disk drive as recited in claim 3, wherein the control circuitry is further operable to verify recoverability of the code segments from the backup area of the disk after aborting a write operation to one of the primary area and backup area of the disk.
8. The disk drive as recited in claim 3, wherein the control circuitry is further operable to verify recoverability of the code segments from the backup area of the disk after executing a number of write operations to one of the primary area and backup area of the disk.
9. The disk drive as recited in claim 1, wherein the control circuitry is further operable to verify recoverability of the code segments from the primary area of the disk when an error occurs while accessing the backup area of the disk.
10. The disk drive as recited in claim 9, wherein the control circuitry is further operable to verify recoverability of the code segments from the primary area of the disk when an error occurs while writing to the backup area of the disk.
11. The disk drive as recited in claim 9, wherein the control circuitry is further operable to verify recoverability of the code segments from the primary area of the disk when a shock event occurs while accessing the backup area of the disk.
12. The disk drive as recited in claim 1, wherein when the verification fails, the control circuitry is further operable to:
relocate a data sector of the backup area to a spare sector of the backup area; and
copy the code segments from the primary area to the spare sector of the backup area.
13. A method of operating a disk drive, the disk drive comprising a disk, and a head actuated over the disk, the method comprising:
writing a plurality of code segments to a primary area of the disk;
writing the code segments to a backup area of the disk;
reading the code segments from the primary area of the disk and execute the code segments read from the primary area of the disk;
after reading the code segments from the primary area of the disk and executing the code segments, verifying recoverability of the code segments from the backup area of the disk; and
when the verification fails, copying the code segments from the primary area of the disk to the backup area of the disk.
14. The method as recited in claim 13, further comprising periodically verifying recoverability of the code segments from the backup area of the disk.
15. The method as recited in claim 13, further comprising verifying recoverability of the code segments from the backup area of the disk when an error occurs while accessing one of the primary area and the backup area of the disk.
16. The method as recited in claim 15, further comprising verifying recoverability of the code segments from the backup area of the disk when a shock event occurs while accessing one of the primary area and backup area of the disk.
17. The method as recited in claim 15, further comprising verifying recoverability of the code segments from the backup area of the disk when an error occurs while reading from the primary area of the disk.
18. The method as recited in claim 15, further comprising verifying recoverability of the code segments from the backup area of the disk when an error occurs while writing to the primary area of the disk.
19. The method as recited in claim 15, further comprising verifying recoverability of the code segments from the backup area of the disk after aborting a write operation to one of the primary area and backup area of the disk.
20. The method as recited in claim 15, further comprising verifying recoverability of the code segments from the backup area of the disk after executing a number of write operations to one of the primary area and backup area of the disk.
21. The method as recited in claim 13, further comprising verifying recoverability of the code segments from the primary area of the disk when an error occurs while accessing the backup area of the disk.
22. The method as recited in claim 21, further comprising verifying recoverability of the code segments from the primary area of the disk when an error occurs while writing to the backup area of the disk.
23. The method as recited in claim 21, further comprising verifying recoverability of the code segments from the primary area of the disk when a shock event occurs while accessing the backup area of the disk.
24. The method as recited in claim 13, wherein when the verification fails, further comprising:
relocating a data sector of the backup area to a spare sector of the backup area; and
copying the code segments from the primary area to the spare sector of the backup area.
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Cited By (124)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8879188B1 (en) 2010-08-23 2014-11-04 Western Digital Technologies, Inc. Disk drive employing fly height calibration tracks to account for magnetic entropy and thermal decay
US8891341B1 (en) 2013-03-11 2014-11-18 Western Digital Technologies, Inc. Energy assisted magnetic recording disk drive using modulated laser light
US8891193B1 (en) 2013-05-09 2014-11-18 Western Digital Technologies, Inc. Disk drive calibrating threshold and gain of touchdown sensor
US8902529B1 (en) 2012-11-20 2014-12-02 Western Digital Technologies, Inc. Dual frequency crystal oscillator
US8902527B1 (en) 2010-03-22 2014-12-02 Western Digital Technologies, Inc. Systems and methods for improving sequential data rate performance using sorted data zones
US8909889B1 (en) 2011-10-10 2014-12-09 Western Digital Technologies, Inc. Method and apparatus for servicing host commands by a disk drive
US8908311B1 (en) 2014-01-27 2014-12-09 Western Digital Technologies, Inc. Data storage device writing a multi-sector codeword in segments over multiple disk revolutions
US8914625B1 (en) 2009-07-31 2014-12-16 Western Digital Technologies, Inc. Automatically configuring a web browser file when booting an operating system from a data storage device
US8922939B1 (en) 2013-04-02 2014-12-30 Western Digital Technologies, Inc. Disk drive generating feed-forward fly height control based on temperature sensitive fly height sensor
US8924775B1 (en) * 2012-09-25 2014-12-30 Western Digital Technologies, Inc. Methods, devices and systems for tracking and relocating intermittently defective disk sectors to prevent indefinite recycling thereof
US8937782B1 (en) 2012-05-07 2015-01-20 Western Digital Technologies, Inc. Hard disk drive assembly including a NVSM to store configuration data for controlling disk drive operations
US8941941B1 (en) 2013-02-28 2015-01-27 Western Digital Technologies, Inc. Disk drive calibrating touchdown sensor
US8949521B1 (en) 2013-04-10 2015-02-03 Western Digital Technologies, Inc. Actuator prepositioning for disk drive
US8947812B1 (en) 2014-03-27 2015-02-03 Western Digital Technologies, Inc. Data storage device comprising equalizer filter and inter-track interference filter
US8953269B1 (en) 2014-07-18 2015-02-10 Western Digital Technologies, Inc. Management of data objects in a data object zone
US8954664B1 (en) 2010-10-01 2015-02-10 Western Digital Technologies, Inc. Writing metadata files on a disk
US8953277B1 (en) 2014-06-16 2015-02-10 Western Digital Technologies, Inc. Data storage device writing tracks on a disk with equal spacing
US8958167B1 (en) 2013-12-23 2015-02-17 Western Digital Technologies, Inc. Detection of disk surface irregularities in data storage devices
US8959281B1 (en) 2012-11-09 2015-02-17 Western Digital Technologies, Inc. Data management for a storage device
US8970978B1 (en) 2012-10-22 2015-03-03 Western Digital Technologies, Inc. Disk drive detecting head touchdown by applying DC+AC control signal to fly height actuator
US8976633B1 (en) 2014-04-15 2015-03-10 Western Digital Technologies, Inc. Data storage device calibrating fly height actuator based on laser power for heat assisted magnetic recording
US8990493B1 (en) 2011-06-30 2015-03-24 Western Digital Technologies, Inc. Method and apparatus for performing force unit access writes on a disk
US8988809B1 (en) 2014-02-18 2015-03-24 Western Digital (Fremont), Llc Disk recording device for writing a radially coherent reference band by measuring relative timing offsets of reference bursts
US8988810B1 (en) 2014-04-16 2015-03-24 Western Digital Technologies, Inc. Track measurement for data storage device
US8996839B1 (en) 2012-01-23 2015-03-31 Western Digital Technologies, Inc. Data storage device aligning partition to boundary of sector when partition offset correlates with offset of write commands
US9001453B1 (en) 2014-07-18 2015-04-07 Western Digital Technologies, Inc. Data storage device calibrating fly height actuator based on read mode touchdown resistance of touchdown sensor
US9009358B1 (en) 2008-09-23 2015-04-14 Western Digital Technologies, Inc. Configuring a data storage device with a parameter file interlocked with configuration code
US9013818B1 (en) 2013-12-06 2015-04-21 Western Digital Technologies, Inc. Disk drive measuring reader/writer gap by measuring fractional clock cycle over disk radius
US9013821B1 (en) 2014-06-10 2015-04-21 Western Digital Technologies, Inc. Data storage device employing one-dimensional and two-dimensional channels
US9021410B1 (en) 2013-12-10 2015-04-28 Western Technologies, Inc. Electronic system with multi-cycle simulation coverage mechanism and method of operation thereof
US9025267B1 (en) 2014-06-09 2015-05-05 Western Digital Technologies, Inc. Data storage device using branch metric from adjacent track to compensate for inter-track interference
US9025270B1 (en) 2013-09-17 2015-05-05 Western Digital Technologies, Inc. Electronic system with current conservation mechanism and method of operation thereof
US9025421B1 (en) 2014-10-08 2015-05-05 Western Digital Technologies, Inc. Data storage device adjusting laser input power to compensate for temperature variations
US9047917B1 (en) 2013-11-26 2015-06-02 Western Digital Technologies, Inc. Disk drive slider with sense amplifier for coupling to a preamp through a supply/bias line and a read signal line
US9049471B2 (en) 2001-10-17 2015-06-02 Keen Personal Media, Inc. Personal video recorder for inserting a stored advertisement into a displayed broadcast stream
US9053730B1 (en) 2012-05-11 2015-06-09 Western Digital Technologies, Inc. Disk drive comprising extended range head proximity sensor
US9053749B1 (en) 2013-03-15 2015-06-09 Western Digital Technologies, Inc. Disk drive comprising a per-drive and per-head fly height filter
US9060420B2 (en) 2007-11-01 2015-06-16 Western Digitial Technologies, Inc. Method of manufacturing a double sided flex circuit for a disk drive wherein a first side lead provides an etching mask for a second side lead
US9064542B1 (en) 2013-04-08 2015-06-23 Western Digital Technologies, Inc. Scheduled load of heads to reduce lubricant migration on pole tip and decrease time to ready
US9064525B2 (en) 2013-11-26 2015-06-23 Western Digital Technologies, Inc. Disk drive comprising laser transmission line optimized for heat assisted magnetic recording
US9064504B1 (en) 2014-01-29 2015-06-23 Western Digital Technologies, Inc. Electronic system with media recovery mechanism and method of operation thereof
US9063838B1 (en) 2012-01-23 2015-06-23 Western Digital Technologies, Inc. Data storage device shifting data chunks of alignment zone relative to sector boundaries
US9070406B1 (en) 2014-03-10 2015-06-30 Western Digital Technologies, Inc. Disk drive configuring one-dimensional and two-dimensional recording areas based on read element spacing
US9074941B1 (en) 2013-03-14 2015-07-07 Western Digital Technologies, Inc. Systems and methods for measuring ambient and laser temperature in heat assisted magnetic recording
US9076474B1 (en) 2014-12-23 2015-07-07 Western Digital Technologies, Inc. Data storage device attenuating thermal decay effect on fly height measurement
US9075714B1 (en) 2014-05-13 2015-07-07 Western Digital Technologies, Inc. Electronic system with data management mechanism and method of operation thereof
US9082458B1 (en) 2014-03-10 2015-07-14 Western Digital Technologies, Inc. Data storage device balancing and maximizing quality metric when configuring arial density of each disk surface
US9099134B1 (en) 2015-01-27 2015-08-04 Western Digital Technologies, Inc. Data storage device employing multiple jog profiles for a butterfly written disk surface
US9099144B1 (en) 2013-10-11 2015-08-04 Western Digital Technologies, Inc. Disk drive evaluating laser performance for heat assisted magnetic recording
US9099103B1 (en) 2014-10-21 2015-08-04 Western Digital Technologies, Inc. Heat assisted magnetic recording withinterlaced high-power heated and low-power heated tracks
US9117463B1 (en) 2014-06-23 2015-08-25 Western Digital Technologies, Inc. Data storage device erasing multiple adjacent data tracks to recover from inter-track interference
US9117479B1 (en) 2014-09-24 2015-08-25 Western Digital Technologies, Inc. Data storage device calibrating laser write power for heat assisted magnetic recording
US9117489B1 (en) 2014-02-18 2015-08-25 Western Digital Technologies, Inc. Data storage device screening heads by verifying defects after defect scan
US9123370B1 (en) 2014-04-15 2015-09-01 Western Digital Technologies, Inc. Data storage device calibrating fly height actuator based on laser power for heat assisted magnetic recording
US9123382B1 (en) 2014-10-28 2015-09-01 Western Digital Technologies, Inc. Non-volatile caching for sequence of data
US9129628B1 (en) 2014-10-23 2015-09-08 Western Digital Technologies, Inc. Data management for data storage device with different track density regions
US9128820B1 (en) 2012-06-18 2015-09-08 Western Digital Technologies, Inc. File management among different zones of storage media
US9135205B1 (en) 2013-05-01 2015-09-15 Western Digital Technologies, Inc. Data storage assembly for archive cold storage
US9153287B1 (en) 2013-05-13 2015-10-06 Western Digital Technologies, Inc. Data access for shingled magnetic recording media
US9153266B1 (en) 2014-09-11 2015-10-06 Western Digital Technologies, Inc. Data storage device measuring laser protrusion fly height profile
US9158722B1 (en) 2011-11-02 2015-10-13 Western Digital Technologies, Inc. Data storage device to communicate with a host in a SATA or a USB mode
US9164694B1 (en) 2013-06-19 2015-10-20 Western Digital Technologies, Inc. Data storage device detecting read-before-write conditions and returning configurable return data
US9171575B1 (en) 2014-06-23 2015-10-27 Western Digital Technologies, Inc. Data storage device detecting media defects by writing opposite polarity test pattern
WO2015165057A1 (en) * 2014-04-30 2015-11-05 华为技术有限公司 Method and device for hard disk drive to execute application code
US9183877B1 (en) 2015-03-20 2015-11-10 Western Digital Technologies, Inc. Data storage device comprising two-dimensional data dependent noise whitening filters for two-dimensional recording
US9183864B1 (en) 2013-06-13 2015-11-10 Western Digital Technologies, Inc. Disk drive adjusting closed-loop fly height target based on change in open-loop fly height control signal
US9189392B1 (en) 2011-06-30 2015-11-17 Western Digital Technologies, Inc. Opportunistic defragmentation during garbage collection
US9196302B1 (en) 2015-03-18 2015-11-24 Western Digital Technologies, Inc. Electronic system with media maintenance mechanism and method of operation thereof
US9214186B1 (en) 2015-03-23 2015-12-15 Western Digital Technologies, Inc. Data storage device measuring radial offset between read element and write element
US9213493B1 (en) 2011-12-16 2015-12-15 Western Digital Technologies, Inc. Sorted serpentine mapping for storage drives
US9230585B1 (en) 2014-01-31 2016-01-05 Western Digital Technologies, Inc. Per wedge preheat DFH to improve data storage device performance
US9230605B1 (en) 2014-12-01 2016-01-05 Western Digital Technologies, Inc. Data storage device maximizing areal density based on a target quality metric
US9236086B1 (en) 2014-10-15 2016-01-12 Western Digital Technologies, Inc. Methods for reducing operational latency of data storage systems
US9245556B2 (en) 2014-03-10 2016-01-26 Western Digital Technologies, Inc. Disk drive employing multiple read elements to increase radial band for two-dimensional magnetic recording
US9245558B1 (en) 2014-05-09 2016-01-26 Western Digital Technologies, Inc. Electronic system with data management mechanism and method of operation thereof
US9251844B1 (en) 2014-06-02 2016-02-02 Western Digital Technologies, Inc. Waterfall method and apparatus for a data storage device read system
US9251856B1 (en) 2014-05-30 2016-02-02 Western Digial Technologies, Inc. Read failover method and apparatus for a data storage system
US9257146B1 (en) 2014-02-11 2016-02-09 Western Digital Technologies, Inc. Data storage device comprising sequence detector compensating for inter-track interference
US9257145B1 (en) 2013-11-27 2016-02-09 Western Digital Technologies, Inc. Disk drive measuring down-track spacing of read sensors
US9257143B1 (en) 2014-12-23 2016-02-09 Western Digital Technologies, Inc. Precautionary measures for data storage device environmental conditions
US9263088B2 (en) 2014-03-21 2016-02-16 Western Digital Technologies, Inc. Data management for a data storage device using a last resort zone
US9269393B1 (en) 2014-12-08 2016-02-23 Western Digital Technologies, Inc. Electronic system with data refresh mechanism and method of operation thereof
US9268499B1 (en) 2010-08-13 2016-02-23 Western Digital Technologies, Inc. Hybrid drive migrating high workload data from disk to non-volatile semiconductor memory
US9268649B1 (en) 2011-06-23 2016-02-23 Western Digital Technologies, Inc. Disk drive with recent write streams list for data refresh determination
US9281009B1 (en) 2014-12-18 2016-03-08 Western Digital Technologies, Inc. Data storage device employing variable size interleave written track segments
US9311939B1 (en) 2014-12-23 2016-04-12 Western Digital Technologies, Inc. Write-through media caching
US9318137B1 (en) 2015-03-13 2016-04-19 Western Digital Technologies, Inc. Data storage device executing retry operation by buffering signal samples at different radial offsets
US9330715B1 (en) 2010-03-22 2016-05-03 Western Digital Technologies, Inc. Mapping of shingled magnetic recording media
US9355666B1 (en) 2013-09-30 2016-05-31 Western Digital Technologies, Inc. Disk drive measuring stroke difference between heads by detecting a difference between ramp contact
US9361938B1 (en) 2015-04-16 2016-06-07 Western Digital Technologies, Inc. Disk defect management for a data storage device
US9368132B1 (en) 2015-09-04 2016-06-14 Western Digital Technologies, Inc. Data storage device employing differential write data signal and differential write pattern signal
US9368131B1 (en) 2015-04-03 2016-06-14 Western Digital (Fremont), Llc Data storage device employing mirrored cross-track profiles for top and bottom disk surfaces
US9383923B1 (en) 2012-10-18 2016-07-05 Western Digital Technologies, Inc. Write pointer management for a disk drive
US9401165B1 (en) 2014-05-05 2016-07-26 Western Digital Technologies, Inc. Method and system to monitor magnetic head loading and unloading stability for a data storage system
US9417628B2 (en) 2013-03-13 2016-08-16 Western Digital Technologies, Inc. Production failure analysis system
US9424864B2 (en) 2014-07-02 2016-08-23 Western Digital Technologies, Inc. Data management for a data storage device with zone relocation
US9437242B1 (en) 2015-09-14 2016-09-06 Western Digital Technologies, Inc. Data storage device employing different frequency preambles in adjacent data tracks
US9466321B1 (en) 2015-06-05 2016-10-11 Western Digital Technologies, Inc. Angular position tracking of data accesses to mitigate risk of data loss
US9466318B2 (en) 2014-12-24 2016-10-11 Western Digital Technologies, Inc. Allowing fast data zone switches on data storage devices
US9472219B1 (en) 2015-05-01 2016-10-18 Western Digital Technologies, Inc. Data storage device calibrating parameter for heat assisted magnetic recording
US9501393B2 (en) 2014-01-27 2016-11-22 Western Digital Technologies, Inc. Data storage system garbage collection based on at least one attribute
US9502068B1 (en) 2015-04-08 2016-11-22 Western Digital Technologies, Inc. Data storage device updating laser power during non-write mode for heat assisted magnetic recording
US9588898B1 (en) 2015-06-02 2017-03-07 Western Digital Technologies, Inc. Fullness control for media-based cache operating in a steady state
US9600205B1 (en) 2014-09-22 2017-03-21 Western Digital Technologies, Inc. Power aware power safe write buffer
US9632711B1 (en) 2014-04-07 2017-04-25 Western Digital Technologies, Inc. Processing flush requests by utilizing storage system write notifications
US9639287B1 (en) 2015-06-29 2017-05-02 Western Digital Technologies, Inc. Write command reporting
US9645752B1 (en) 2014-04-07 2017-05-09 Western Digital Technologies, Inc. Identification of data committed to non-volatile memory by use of notification commands
US9672107B1 (en) 2015-02-11 2017-06-06 Western Digital Technologies, Inc. Data protection for a data storage device
US9747928B1 (en) 2014-09-25 2017-08-29 Western Digital Technologies, Inc. Data storage device modifying write operation when a laser mode hop is detected
US9761273B1 (en) 2015-11-03 2017-09-12 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection
US9842622B1 (en) 2014-12-23 2017-12-12 Western Digital Technologies, Inc. Data storage device having improved read failure tolerance
US9842617B1 (en) 2015-06-29 2017-12-12 Western Digital Technologies, Inc. Electronic system with head management mechanism and method of operation thereof
US9864529B1 (en) 2014-01-27 2018-01-09 Western Digital Technologies, Inc. Host compatibility for host managed storage media
US9870281B1 (en) 2015-03-20 2018-01-16 Western Digital Technologies, Inc. Power loss mitigation for data storage device
US9875055B1 (en) 2014-08-04 2018-01-23 Western Digital Technologies, Inc. Check-pointing of metadata
US9916616B2 (en) 2014-03-31 2018-03-13 Western Digital Technologies, Inc. Inventory management system using incremental capacity formats
US9933955B1 (en) 2015-03-05 2018-04-03 Western Digital Technologies, Inc. Power safe write buffer for data storage device
US9952950B1 (en) 2014-09-08 2018-04-24 Western Digital Technologies, Inc. Data management in RAID environment
US9959052B1 (en) 2015-09-17 2018-05-01 Western Digital Technologies, Inc. Media based cache for data storage device
US10056920B1 (en) 2015-11-03 2018-08-21 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection
US10063257B1 (en) 2015-11-03 2018-08-28 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection
US10282096B1 (en) 2014-12-17 2019-05-07 Western Digital Technologies, Inc. Identification of data with predetermined data pattern
US10282371B1 (en) 2014-12-02 2019-05-07 Western Digital Technologies, Inc. Object storage device with probabilistic data structure
US10365836B1 (en) 2015-01-27 2019-07-30 Western Digital Technologies, Inc. Electronic system with declustered data protection by parity based on reliability and method of operation thereof

Citations (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5392290A (en) 1992-07-30 1995-02-21 International Business Machines Corporation System and method for preventing direct access data storage system data loss from mechanical shock during write operation
US5729696A (en) * 1995-06-13 1998-03-17 Ncr Corporation Transaction data recovery system and method
US5895493A (en) 1997-06-30 1999-04-20 Lsi Logic Corporation Method and apparatus for storage of multiple host storage management information on a storage subsystem
US5966732A (en) 1996-12-02 1999-10-12 Gateway 2000, Inc. Method and apparatus for adding to the reserve area of a disk drive
US6167494A (en) 1998-04-28 2000-12-26 International Business Machine Corporation Method and system for recovering from operating system failure
US6185678B1 (en) * 1997-10-02 2001-02-06 Trustees Of The University Of Pennsylvania Secure and reliable bootstrap architecture
US6279117B1 (en) * 1997-10-31 2001-08-21 Hitachi, Ltd. Recovery support method for recovering from failure of an external storage device
US6320718B1 (en) 1999-01-07 2001-11-20 Western Digital Technologies, Inc. Disk drive with zero read offset in reserved area and method of making same
US6384999B1 (en) 1999-04-12 2002-05-07 Western Digital Technologies, Inc. Rewrite with embedded reassign for data recovery from marginally defective data sites on a data storage device
US6513135B2 (en) 2000-08-02 2003-01-28 Hitachi, Ltd. Automatic read reassignment method and a magnetic disk drive
US6560701B1 (en) 1997-02-10 2003-05-06 International Business Machines Corporation Alternate boot record
US6650492B2 (en) 2000-09-28 2003-11-18 Seagate Technology Llc Self-contained disc drive write authentication test
US20030217300A1 (en) * 2002-04-30 2003-11-20 Hitachi, Ltd. Method for backing up power supply of disk array device and system thereof
US20030229819A1 (en) * 2002-06-11 2003-12-11 Hitachi, Ltd. Method and apparatus for data backup and recovery
US20030236956A1 (en) * 2002-06-20 2003-12-25 International Business Machines Corpoaration File system backup in a logical volume management data storage environment
US6728830B1 (en) 2000-08-25 2004-04-27 Gateway, Inc. Method and apparatus for modifying the reserve area of a disk drive
US6732124B1 (en) * 1999-03-30 2004-05-04 Fujitsu Limited Data processing system with mechanism for restoring file systems based on transaction logs
US6760823B1 (en) * 2001-02-05 2004-07-06 Emc Corporation File mapping system and related techniques
US20050010620A1 (en) * 2003-05-30 2005-01-13 Veritas Software Corporation Multi-volume file support
US20050021919A1 (en) 2003-07-24 2005-01-27 Kroening James L. Save and restore of a protected area
US20050027935A1 (en) 2003-02-05 2005-02-03 Samsung Electronics Co., Ltd. Single head disk drive having backup system information and method of recording and/or reading system information thereof
US6868496B2 (en) 2001-01-16 2005-03-15 Gateway, Inc. Host protected area (HPA) duplication process
US6880102B1 (en) * 1998-10-23 2005-04-12 Oracle International Corporation Method and system for managing storage systems containing multiple data storage devices
US6883073B2 (en) * 2002-01-09 2005-04-19 Hitachi, Ltd. Virtualized volume snapshot formation method
US20050108485A1 (en) * 2003-11-18 2005-05-19 Perego Robert M. Data set level mirroring to accomplish a volume merge/migrate in a digital data storage system
US20050216681A1 (en) * 2004-03-29 2005-09-29 International Business Machines Corporation Method, system, and article of manufacture for copying of data in a romote storage unit
US20050246401A1 (en) * 2004-04-30 2005-11-03 Edwards John K Extension of write anywhere file system layout
US6963951B2 (en) 2000-07-12 2005-11-08 Seagate Technology Llc Partition recovery method
US20060041738A1 (en) * 2004-08-17 2006-02-23 Yu-Chen Lai Recovery method for master boot record of hard disk drive
US20060248295A1 (en) * 2005-04-27 2006-11-02 Takashi Uchiyama Storage system and backup method
US7139145B1 (en) 2004-09-23 2006-11-21 Western Digital Technologies, Inc. Cluster-based defect detection testing for disk drives
US20070011493A1 (en) 2003-05-06 2007-01-11 Lenovo (Beijing) Limited Method for renovating the computer operating system
US7173782B2 (en) 2004-03-17 2007-02-06 Hitachi Global Storage Technologies Netherlands, B.V. Magnetic disk drive and refresh method
US7219257B1 (en) 2003-06-27 2007-05-15 Adaptec, Inc. Method for boot recovery
US7296142B2 (en) 2003-06-24 2007-11-13 Seagate Technology Llc Multi-tiered retry scheme for reading copies of information from a storage medium
US7302579B1 (en) 2004-03-31 2007-11-27 Western Digital Technologies, Inc. Performing backup operations to peripheral data storage systems
US7313725B2 (en) 2003-07-29 2007-12-25 Gateway Inc. Replacement restoration disk drive and method
US7360113B2 (en) * 2004-08-30 2008-04-15 Mendocino Software, Inc. Protocol for communicating data block copies in an error recovery environment
US7613946B2 (en) * 2006-09-14 2009-11-03 International Business Machines Corporation Apparatus, system, and method for recovering a multivolume data set
US7707184B1 (en) * 2002-10-09 2010-04-27 Netapp, Inc. System and method for snapshot full backup and hard recovery of a database

Patent Citations (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5392290A (en) 1992-07-30 1995-02-21 International Business Machines Corporation System and method for preventing direct access data storage system data loss from mechanical shock during write operation
US5729696A (en) * 1995-06-13 1998-03-17 Ncr Corporation Transaction data recovery system and method
US5966732A (en) 1996-12-02 1999-10-12 Gateway 2000, Inc. Method and apparatus for adding to the reserve area of a disk drive
US6560701B1 (en) 1997-02-10 2003-05-06 International Business Machines Corporation Alternate boot record
US5895493A (en) 1997-06-30 1999-04-20 Lsi Logic Corporation Method and apparatus for storage of multiple host storage management information on a storage subsystem
US6185678B1 (en) * 1997-10-02 2001-02-06 Trustees Of The University Of Pennsylvania Secure and reliable bootstrap architecture
US6279117B1 (en) * 1997-10-31 2001-08-21 Hitachi, Ltd. Recovery support method for recovering from failure of an external storage device
US6167494A (en) 1998-04-28 2000-12-26 International Business Machine Corporation Method and system for recovering from operating system failure
US6880102B1 (en) * 1998-10-23 2005-04-12 Oracle International Corporation Method and system for managing storage systems containing multiple data storage devices
US6320718B1 (en) 1999-01-07 2001-11-20 Western Digital Technologies, Inc. Disk drive with zero read offset in reserved area and method of making same
US6732124B1 (en) * 1999-03-30 2004-05-04 Fujitsu Limited Data processing system with mechanism for restoring file systems based on transaction logs
US6384999B1 (en) 1999-04-12 2002-05-07 Western Digital Technologies, Inc. Rewrite with embedded reassign for data recovery from marginally defective data sites on a data storage device
US6963951B2 (en) 2000-07-12 2005-11-08 Seagate Technology Llc Partition recovery method
US6513135B2 (en) 2000-08-02 2003-01-28 Hitachi, Ltd. Automatic read reassignment method and a magnetic disk drive
US6728830B1 (en) 2000-08-25 2004-04-27 Gateway, Inc. Method and apparatus for modifying the reserve area of a disk drive
US6650492B2 (en) 2000-09-28 2003-11-18 Seagate Technology Llc Self-contained disc drive write authentication test
US6868496B2 (en) 2001-01-16 2005-03-15 Gateway, Inc. Host protected area (HPA) duplication process
US6760823B1 (en) * 2001-02-05 2004-07-06 Emc Corporation File mapping system and related techniques
US6883073B2 (en) * 2002-01-09 2005-04-19 Hitachi, Ltd. Virtualized volume snapshot formation method
US7051233B2 (en) * 2002-04-30 2006-05-23 Hitachi, Ltd. Method for backing up power supply of disk array device and system thereof
US20030217300A1 (en) * 2002-04-30 2003-11-20 Hitachi, Ltd. Method for backing up power supply of disk array device and system thereof
US6944789B2 (en) * 2002-06-11 2005-09-13 Hitachi, Ltd. Method and apparatus for data backup and recovery
US20030229819A1 (en) * 2002-06-11 2003-12-11 Hitachi, Ltd. Method and apparatus for data backup and recovery
US20030236956A1 (en) * 2002-06-20 2003-12-25 International Business Machines Corpoaration File system backup in a logical volume management data storage environment
US7707184B1 (en) * 2002-10-09 2010-04-27 Netapp, Inc. System and method for snapshot full backup and hard recovery of a database
US20050027935A1 (en) 2003-02-05 2005-02-03 Samsung Electronics Co., Ltd. Single head disk drive having backup system information and method of recording and/or reading system information thereof
US20070011493A1 (en) 2003-05-06 2007-01-11 Lenovo (Beijing) Limited Method for renovating the computer operating system
US20050010620A1 (en) * 2003-05-30 2005-01-13 Veritas Software Corporation Multi-volume file support
US7296142B2 (en) 2003-06-24 2007-11-13 Seagate Technology Llc Multi-tiered retry scheme for reading copies of information from a storage medium
US7219257B1 (en) 2003-06-27 2007-05-15 Adaptec, Inc. Method for boot recovery
US20050021919A1 (en) 2003-07-24 2005-01-27 Kroening James L. Save and restore of a protected area
US7313725B2 (en) 2003-07-29 2007-12-25 Gateway Inc. Replacement restoration disk drive and method
US20050108485A1 (en) * 2003-11-18 2005-05-19 Perego Robert M. Data set level mirroring to accomplish a volume merge/migrate in a digital data storage system
US7173782B2 (en) 2004-03-17 2007-02-06 Hitachi Global Storage Technologies Netherlands, B.V. Magnetic disk drive and refresh method
US20050216681A1 (en) * 2004-03-29 2005-09-29 International Business Machines Corporation Method, system, and article of manufacture for copying of data in a romote storage unit
US7302579B1 (en) 2004-03-31 2007-11-27 Western Digital Technologies, Inc. Performing backup operations to peripheral data storage systems
US20050246401A1 (en) * 2004-04-30 2005-11-03 Edwards John K Extension of write anywhere file system layout
US20060041738A1 (en) * 2004-08-17 2006-02-23 Yu-Chen Lai Recovery method for master boot record of hard disk drive
US7360113B2 (en) * 2004-08-30 2008-04-15 Mendocino Software, Inc. Protocol for communicating data block copies in an error recovery environment
US7139145B1 (en) 2004-09-23 2006-11-21 Western Digital Technologies, Inc. Cluster-based defect detection testing for disk drives
US20060248295A1 (en) * 2005-04-27 2006-11-02 Takashi Uchiyama Storage system and backup method
US7613946B2 (en) * 2006-09-14 2009-11-03 International Business Machines Corporation Apparatus, system, and method for recovering a multivolume data set

Cited By (136)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9049471B2 (en) 2001-10-17 2015-06-02 Keen Personal Media, Inc. Personal video recorder for inserting a stored advertisement into a displayed broadcast stream
US9060420B2 (en) 2007-11-01 2015-06-16 Western Digitial Technologies, Inc. Method of manufacturing a double sided flex circuit for a disk drive wherein a first side lead provides an etching mask for a second side lead
US9009358B1 (en) 2008-09-23 2015-04-14 Western Digital Technologies, Inc. Configuring a data storage device with a parameter file interlocked with configuration code
US8914625B1 (en) 2009-07-31 2014-12-16 Western Digital Technologies, Inc. Automatically configuring a web browser file when booting an operating system from a data storage device
US8902527B1 (en) 2010-03-22 2014-12-02 Western Digital Technologies, Inc. Systems and methods for improving sequential data rate performance using sorted data zones
US9330715B1 (en) 2010-03-22 2016-05-03 Western Digital Technologies, Inc. Mapping of shingled magnetic recording media
US9268499B1 (en) 2010-08-13 2016-02-23 Western Digital Technologies, Inc. Hybrid drive migrating high workload data from disk to non-volatile semiconductor memory
US8879188B1 (en) 2010-08-23 2014-11-04 Western Digital Technologies, Inc. Disk drive employing fly height calibration tracks to account for magnetic entropy and thermal decay
US8954664B1 (en) 2010-10-01 2015-02-10 Western Digital Technologies, Inc. Writing metadata files on a disk
US9268649B1 (en) 2011-06-23 2016-02-23 Western Digital Technologies, Inc. Disk drive with recent write streams list for data refresh determination
US8990493B1 (en) 2011-06-30 2015-03-24 Western Digital Technologies, Inc. Method and apparatus for performing force unit access writes on a disk
US9189392B1 (en) 2011-06-30 2015-11-17 Western Digital Technologies, Inc. Opportunistic defragmentation during garbage collection
US8909889B1 (en) 2011-10-10 2014-12-09 Western Digital Technologies, Inc. Method and apparatus for servicing host commands by a disk drive
US9158722B1 (en) 2011-11-02 2015-10-13 Western Digital Technologies, Inc. Data storage device to communicate with a host in a SATA or a USB mode
US9213493B1 (en) 2011-12-16 2015-12-15 Western Digital Technologies, Inc. Sorted serpentine mapping for storage drives
US9063838B1 (en) 2012-01-23 2015-06-23 Western Digital Technologies, Inc. Data storage device shifting data chunks of alignment zone relative to sector boundaries
US8996839B1 (en) 2012-01-23 2015-03-31 Western Digital Technologies, Inc. Data storage device aligning partition to boundary of sector when partition offset correlates with offset of write commands
US8937782B1 (en) 2012-05-07 2015-01-20 Western Digital Technologies, Inc. Hard disk drive assembly including a NVSM to store configuration data for controlling disk drive operations
US9053730B1 (en) 2012-05-11 2015-06-09 Western Digital Technologies, Inc. Disk drive comprising extended range head proximity sensor
US9128820B1 (en) 2012-06-18 2015-09-08 Western Digital Technologies, Inc. File management among different zones of storage media
US9477681B2 (en) 2012-06-18 2016-10-25 Western Digital Technologies, Inc. File management among different zones of storage media
US8924775B1 (en) * 2012-09-25 2014-12-30 Western Digital Technologies, Inc. Methods, devices and systems for tracking and relocating intermittently defective disk sectors to prevent indefinite recycling thereof
US9383923B1 (en) 2012-10-18 2016-07-05 Western Digital Technologies, Inc. Write pointer management for a disk drive
US8970978B1 (en) 2012-10-22 2015-03-03 Western Digital Technologies, Inc. Disk drive detecting head touchdown by applying DC+AC control signal to fly height actuator
US8959281B1 (en) 2012-11-09 2015-02-17 Western Digital Technologies, Inc. Data management for a storage device
US8902529B1 (en) 2012-11-20 2014-12-02 Western Digital Technologies, Inc. Dual frequency crystal oscillator
US8941941B1 (en) 2013-02-28 2015-01-27 Western Digital Technologies, Inc. Disk drive calibrating touchdown sensor
US8891341B1 (en) 2013-03-11 2014-11-18 Western Digital Technologies, Inc. Energy assisted magnetic recording disk drive using modulated laser light
US9417628B2 (en) 2013-03-13 2016-08-16 Western Digital Technologies, Inc. Production failure analysis system
US9074941B1 (en) 2013-03-14 2015-07-07 Western Digital Technologies, Inc. Systems and methods for measuring ambient and laser temperature in heat assisted magnetic recording
US9053749B1 (en) 2013-03-15 2015-06-09 Western Digital Technologies, Inc. Disk drive comprising a per-drive and per-head fly height filter
US8922939B1 (en) 2013-04-02 2014-12-30 Western Digital Technologies, Inc. Disk drive generating feed-forward fly height control based on temperature sensitive fly height sensor
US9064542B1 (en) 2013-04-08 2015-06-23 Western Digital Technologies, Inc. Scheduled load of heads to reduce lubricant migration on pole tip and decrease time to ready
US8949521B1 (en) 2013-04-10 2015-02-03 Western Digital Technologies, Inc. Actuator prepositioning for disk drive
US9135205B1 (en) 2013-05-01 2015-09-15 Western Digital Technologies, Inc. Data storage assembly for archive cold storage
US8891193B1 (en) 2013-05-09 2014-11-18 Western Digital Technologies, Inc. Disk drive calibrating threshold and gain of touchdown sensor
US9153287B1 (en) 2013-05-13 2015-10-06 Western Digital Technologies, Inc. Data access for shingled magnetic recording media
US9183864B1 (en) 2013-06-13 2015-11-10 Western Digital Technologies, Inc. Disk drive adjusting closed-loop fly height target based on change in open-loop fly height control signal
US9164694B1 (en) 2013-06-19 2015-10-20 Western Digital Technologies, Inc. Data storage device detecting read-before-write conditions and returning configurable return data
US9025270B1 (en) 2013-09-17 2015-05-05 Western Digital Technologies, Inc. Electronic system with current conservation mechanism and method of operation thereof
US9355666B1 (en) 2013-09-30 2016-05-31 Western Digital Technologies, Inc. Disk drive measuring stroke difference between heads by detecting a difference between ramp contact
US9099144B1 (en) 2013-10-11 2015-08-04 Western Digital Technologies, Inc. Disk drive evaluating laser performance for heat assisted magnetic recording
US9299371B1 (en) 2013-11-26 2016-03-29 Western Digital Technologies, Inc. Disk drive slider with sense amplifier for coupling to a preamp through a supply/bias line and a read signal line
US9047917B1 (en) 2013-11-26 2015-06-02 Western Digital Technologies, Inc. Disk drive slider with sense amplifier for coupling to a preamp through a supply/bias line and a read signal line
US9064525B2 (en) 2013-11-26 2015-06-23 Western Digital Technologies, Inc. Disk drive comprising laser transmission line optimized for heat assisted magnetic recording
US9257145B1 (en) 2013-11-27 2016-02-09 Western Digital Technologies, Inc. Disk drive measuring down-track spacing of read sensors
US9013818B1 (en) 2013-12-06 2015-04-21 Western Digital Technologies, Inc. Disk drive measuring reader/writer gap by measuring fractional clock cycle over disk radius
US9021410B1 (en) 2013-12-10 2015-04-28 Western Technologies, Inc. Electronic system with multi-cycle simulation coverage mechanism and method of operation thereof
US8958167B1 (en) 2013-12-23 2015-02-17 Western Digital Technologies, Inc. Detection of disk surface irregularities in data storage devices
US8908311B1 (en) 2014-01-27 2014-12-09 Western Digital Technologies, Inc. Data storage device writing a multi-sector codeword in segments over multiple disk revolutions
US10282130B2 (en) 2014-01-27 2019-05-07 Western Digital Technologies, Inc. Coherency of data in data relocation
US9864529B1 (en) 2014-01-27 2018-01-09 Western Digital Technologies, Inc. Host compatibility for host managed storage media
US9501393B2 (en) 2014-01-27 2016-11-22 Western Digital Technologies, Inc. Data storage system garbage collection based on at least one attribute
US9064504B1 (en) 2014-01-29 2015-06-23 Western Digital Technologies, Inc. Electronic system with media recovery mechanism and method of operation thereof
US9230585B1 (en) 2014-01-31 2016-01-05 Western Digital Technologies, Inc. Per wedge preheat DFH to improve data storage device performance
US9257146B1 (en) 2014-02-11 2016-02-09 Western Digital Technologies, Inc. Data storage device comprising sequence detector compensating for inter-track interference
US8988809B1 (en) 2014-02-18 2015-03-24 Western Digital (Fremont), Llc Disk recording device for writing a radially coherent reference band by measuring relative timing offsets of reference bursts
US9117489B1 (en) 2014-02-18 2015-08-25 Western Digital Technologies, Inc. Data storage device screening heads by verifying defects after defect scan
US9070406B1 (en) 2014-03-10 2015-06-30 Western Digital Technologies, Inc. Disk drive configuring one-dimensional and two-dimensional recording areas based on read element spacing
US9082458B1 (en) 2014-03-10 2015-07-14 Western Digital Technologies, Inc. Data storage device balancing and maximizing quality metric when configuring arial density of each disk surface
US9245556B2 (en) 2014-03-10 2016-01-26 Western Digital Technologies, Inc. Disk drive employing multiple read elements to increase radial band for two-dimensional magnetic recording
US9263088B2 (en) 2014-03-21 2016-02-16 Western Digital Technologies, Inc. Data management for a data storage device using a last resort zone
US8947812B1 (en) 2014-03-27 2015-02-03 Western Digital Technologies, Inc. Data storage device comprising equalizer filter and inter-track interference filter
US9916616B2 (en) 2014-03-31 2018-03-13 Western Digital Technologies, Inc. Inventory management system using incremental capacity formats
US9645752B1 (en) 2014-04-07 2017-05-09 Western Digital Technologies, Inc. Identification of data committed to non-volatile memory by use of notification commands
US9632711B1 (en) 2014-04-07 2017-04-25 Western Digital Technologies, Inc. Processing flush requests by utilizing storage system write notifications
US10162534B1 (en) 2014-04-07 2018-12-25 Western Digital Technologies, Inc. Ordering commitment of data from a data cache to nonvolatile memory using ordering commands
US9123370B1 (en) 2014-04-15 2015-09-01 Western Digital Technologies, Inc. Data storage device calibrating fly height actuator based on laser power for heat assisted magnetic recording
US8976633B1 (en) 2014-04-15 2015-03-10 Western Digital Technologies, Inc. Data storage device calibrating fly height actuator based on laser power for heat assisted magnetic recording
US8988810B1 (en) 2014-04-16 2015-03-24 Western Digital Technologies, Inc. Track measurement for data storage device
CN105247618B (en) * 2014-04-30 2017-12-15 华为技术有限公司 A kind of hard disk performs the method and device of application code
US10310876B2 (en) 2014-04-30 2019-06-04 Huawei Technologies Co., Ltd. Executing application code based on manner of accessing a hard disk
CN105247618A (en) * 2014-04-30 2016-01-13 华为技术有限公司 Method and device for hard disk drive to execute application code
WO2015165057A1 (en) * 2014-04-30 2015-11-05 华为技术有限公司 Method and device for hard disk drive to execute application code
US9401165B1 (en) 2014-05-05 2016-07-26 Western Digital Technologies, Inc. Method and system to monitor magnetic head loading and unloading stability for a data storage system
US9245558B1 (en) 2014-05-09 2016-01-26 Western Digital Technologies, Inc. Electronic system with data management mechanism and method of operation thereof
US9075714B1 (en) 2014-05-13 2015-07-07 Western Digital Technologies, Inc. Electronic system with data management mechanism and method of operation thereof
US9251856B1 (en) 2014-05-30 2016-02-02 Western Digial Technologies, Inc. Read failover method and apparatus for a data storage system
US9251844B1 (en) 2014-06-02 2016-02-02 Western Digital Technologies, Inc. Waterfall method and apparatus for a data storage device read system
US9025267B1 (en) 2014-06-09 2015-05-05 Western Digital Technologies, Inc. Data storage device using branch metric from adjacent track to compensate for inter-track interference
US9013821B1 (en) 2014-06-10 2015-04-21 Western Digital Technologies, Inc. Data storage device employing one-dimensional and two-dimensional channels
US8953277B1 (en) 2014-06-16 2015-02-10 Western Digital Technologies, Inc. Data storage device writing tracks on a disk with equal spacing
US9117463B1 (en) 2014-06-23 2015-08-25 Western Digital Technologies, Inc. Data storage device erasing multiple adjacent data tracks to recover from inter-track interference
US9171575B1 (en) 2014-06-23 2015-10-27 Western Digital Technologies, Inc. Data storage device detecting media defects by writing opposite polarity test pattern
US9424864B2 (en) 2014-07-02 2016-08-23 Western Digital Technologies, Inc. Data management for a data storage device with zone relocation
US9001453B1 (en) 2014-07-18 2015-04-07 Western Digital Technologies, Inc. Data storage device calibrating fly height actuator based on read mode touchdown resistance of touchdown sensor
US8953269B1 (en) 2014-07-18 2015-02-10 Western Digital Technologies, Inc. Management of data objects in a data object zone
US9875055B1 (en) 2014-08-04 2018-01-23 Western Digital Technologies, Inc. Check-pointing of metadata
US10572358B1 (en) 2014-09-08 2020-02-25 Western Digital Technologies, Inc. Data management in RAID environment
US9952950B1 (en) 2014-09-08 2018-04-24 Western Digital Technologies, Inc. Data management in RAID environment
US9153266B1 (en) 2014-09-11 2015-10-06 Western Digital Technologies, Inc. Data storage device measuring laser protrusion fly height profile
US9600205B1 (en) 2014-09-22 2017-03-21 Western Digital Technologies, Inc. Power aware power safe write buffer
US9117479B1 (en) 2014-09-24 2015-08-25 Western Digital Technologies, Inc. Data storage device calibrating laser write power for heat assisted magnetic recording
US9972344B2 (en) 2014-09-25 2018-05-15 Western Digital Technologies, Inc. Data storage device modifying write operation when a laser mode hop is detected
US9747928B1 (en) 2014-09-25 2017-08-29 Western Digital Technologies, Inc. Data storage device modifying write operation when a laser mode hop is detected
US9025421B1 (en) 2014-10-08 2015-05-05 Western Digital Technologies, Inc. Data storage device adjusting laser input power to compensate for temperature variations
US9236086B1 (en) 2014-10-15 2016-01-12 Western Digital Technologies, Inc. Methods for reducing operational latency of data storage systems
US9099103B1 (en) 2014-10-21 2015-08-04 Western Digital Technologies, Inc. Heat assisted magnetic recording withinterlaced high-power heated and low-power heated tracks
US9129628B1 (en) 2014-10-23 2015-09-08 Western Digital Technologies, Inc. Data management for data storage device with different track density regions
US9123382B1 (en) 2014-10-28 2015-09-01 Western Digital Technologies, Inc. Non-volatile caching for sequence of data
US9230605B1 (en) 2014-12-01 2016-01-05 Western Digital Technologies, Inc. Data storage device maximizing areal density based on a target quality metric
US10282371B1 (en) 2014-12-02 2019-05-07 Western Digital Technologies, Inc. Object storage device with probabilistic data structure
US9269393B1 (en) 2014-12-08 2016-02-23 Western Digital Technologies, Inc. Electronic system with data refresh mechanism and method of operation thereof
US10282096B1 (en) 2014-12-17 2019-05-07 Western Digital Technologies, Inc. Identification of data with predetermined data pattern
US9281009B1 (en) 2014-12-18 2016-03-08 Western Digital Technologies, Inc. Data storage device employing variable size interleave written track segments
US9311939B1 (en) 2014-12-23 2016-04-12 Western Digital Technologies, Inc. Write-through media caching
US9257143B1 (en) 2014-12-23 2016-02-09 Western Digital Technologies, Inc. Precautionary measures for data storage device environmental conditions
US9842622B1 (en) 2014-12-23 2017-12-12 Western Digital Technologies, Inc. Data storage device having improved read failure tolerance
US9076474B1 (en) 2014-12-23 2015-07-07 Western Digital Technologies, Inc. Data storage device attenuating thermal decay effect on fly height measurement
US9466318B2 (en) 2014-12-24 2016-10-11 Western Digital Technologies, Inc. Allowing fast data zone switches on data storage devices
US9099134B1 (en) 2015-01-27 2015-08-04 Western Digital Technologies, Inc. Data storage device employing multiple jog profiles for a butterfly written disk surface
US10365836B1 (en) 2015-01-27 2019-07-30 Western Digital Technologies, Inc. Electronic system with declustered data protection by parity based on reliability and method of operation thereof
US9672107B1 (en) 2015-02-11 2017-06-06 Western Digital Technologies, Inc. Data protection for a data storage device
US9933955B1 (en) 2015-03-05 2018-04-03 Western Digital Technologies, Inc. Power safe write buffer for data storage device
US9318137B1 (en) 2015-03-13 2016-04-19 Western Digital Technologies, Inc. Data storage device executing retry operation by buffering signal samples at different radial offsets
US9196302B1 (en) 2015-03-18 2015-11-24 Western Digital Technologies, Inc. Electronic system with media maintenance mechanism and method of operation thereof
US9183877B1 (en) 2015-03-20 2015-11-10 Western Digital Technologies, Inc. Data storage device comprising two-dimensional data dependent noise whitening filters for two-dimensional recording
US9870281B1 (en) 2015-03-20 2018-01-16 Western Digital Technologies, Inc. Power loss mitigation for data storage device
US9384774B1 (en) 2015-03-23 2016-07-05 Western Digital Technologies, Inc. Data storage device calibrating a laser power for heat assisted magnetic recording based on slope of quality metric
US9214186B1 (en) 2015-03-23 2015-12-15 Western Digital Technologies, Inc. Data storage device measuring radial offset between read element and write element
US9368131B1 (en) 2015-04-03 2016-06-14 Western Digital (Fremont), Llc Data storage device employing mirrored cross-track profiles for top and bottom disk surfaces
US9502068B1 (en) 2015-04-08 2016-11-22 Western Digital Technologies, Inc. Data storage device updating laser power during non-write mode for heat assisted magnetic recording
US9361938B1 (en) 2015-04-16 2016-06-07 Western Digital Technologies, Inc. Disk defect management for a data storage device
US9472219B1 (en) 2015-05-01 2016-10-18 Western Digital Technologies, Inc. Data storage device calibrating parameter for heat assisted magnetic recording
US9588898B1 (en) 2015-06-02 2017-03-07 Western Digital Technologies, Inc. Fullness control for media-based cache operating in a steady state
US9466321B1 (en) 2015-06-05 2016-10-11 Western Digital Technologies, Inc. Angular position tracking of data accesses to mitigate risk of data loss
US9842617B1 (en) 2015-06-29 2017-12-12 Western Digital Technologies, Inc. Electronic system with head management mechanism and method of operation thereof
US9639287B1 (en) 2015-06-29 2017-05-02 Western Digital Technologies, Inc. Write command reporting
US9368132B1 (en) 2015-09-04 2016-06-14 Western Digital Technologies, Inc. Data storage device employing differential write data signal and differential write pattern signal
US9437242B1 (en) 2015-09-14 2016-09-06 Western Digital Technologies, Inc. Data storage device employing different frequency preambles in adjacent data tracks
US9959052B1 (en) 2015-09-17 2018-05-01 Western Digital Technologies, Inc. Media based cache for data storage device
US10063257B1 (en) 2015-11-03 2018-08-28 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection
US10056920B1 (en) 2015-11-03 2018-08-21 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection
US9761273B1 (en) 2015-11-03 2017-09-12 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection
US10554221B2 (en) 2015-11-03 2020-02-04 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection
US10554225B2 (en) 2015-11-03 2020-02-04 Western Digital Technologies, Inc. Data storage device encoding and interleaving codewords to improve trellis sequence detection

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